discovery: Explicitly close opened files (#28859)

Author: vitkyrka

pkg/collector/corechecks/servicediscovery/usm/nodejs.go

@@ -96,6 +96,7 @@ func (n nodeDetector) maybeExtractServiceName(filename string) (string, bool) {
 	if err != nil {
 		return "", false
 	}
+	defer file.Close()
 	ok, err := canSafelyParse(file)
 	if err != nil {
 		//file not accessible or don't exist. Continuing searching up

pkg/collector/corechecks/servicediscovery/usm/tomcat.go

@@ -132,6 +132,7 @@ func (te tomcatExtractor) parseServerXML(domainHome string) *tomcatServerXML {
 		log.Debugf("Unable to locate tomcat server.xml (%q). Err: %v", xmlFilePath, err)
 		return nil
 	}
+	defer file.Close()
 	var serverXML tomcatServerXML
 	err = xml.NewDecoder(file).Decode(&serverXML)
 	if err != nil {